Making use of clamp angle goal

Hi there a quick question on the clamp angle goal. Are all angles with respect to the start to end direction vector of line A?

I have set up my model based on this, I am constraining everything to a plane. The start direction is a given angle, and the upper limit angle is larger than this and +ve. The lower limit I would like to make -ve and this seems to cause me problems.

Am I thinking of this in the right way?

Slow down and take the time to compose your question more clearly. Take as much time (or more) than anyone will spend trying to answer it.

My question is, what are the angles in the clamp angle with respect to?

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